Some Ans. Questions 2014 by -'Abdu'l-Bahá- 1 Para

As I have already explained the meaning of "day", no further explanation is needed, but let me briefly say that each day of the Father is equivalent to one year, and each year consists of twelve months. Thus three and a half years makes forty-two months, and forty-two months is 1,260 days, and each day in the Bible is equivalent to one year. And it is in the very year 1260 from the emigration of Muhammad, according to the Muslim calendar, that the Bab, the Herald of Baha'u'llah, revealed His mission (10:20)

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